Centos 6 单机 ORACLE 11g 修改 hostname OEM 无法正常运行问题处理

原创 lps 2024-09-15

适用范围

Centos 6 单机 ORACLE 11g 安装完成时候，需要修改修改主机名称，修改主机名称后，OEM 无法正常运行的问题处理。

问题概述

Centos 6 单机修改主机名称

Centos 6 修改主机名称是需要修改配置文件的，跟 Centos/rhel 7 系列不一样，7 系列是可以通过 hostnamectl set-hostname namexx 来直接修改，不管是 6 系列还是 7 系列修改主机名称之后，都要手工修改/etc/hosts 下配置的 hostname。

在修改主机名称这一块，对于是否需要重启主机来说，有些许争议，这里我搜索了官方文档，找到了 rhel 7 系列的修改主机名称的文档：https://docs.redhat.com/en/documentation/red_hat_enterprise_linux/8/html/configuring_and_managing_networking/assembly_changing-a-hostname_configuring-and-managing-networking#proc_changing-a-hostname-using-hostnamectl_assembly_changing-a-hostname

The hostnamectl utility automatically restarts the systemd-hostnamed to activate the new name. For the changes to take effect, reboot the host:
# reboot
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Alternatively, if you know which services use the hostname:
Restart all services that only read the hostname when the service starts:
# systemctl restart <service_name>
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Active shell users must re-login for the changes to take effect.

这里有写需要重启reboot主机生效，或者重启某个读到 hostname 的服务。

在这里生产环境建议重启下主机生效，也不知道那些服务用到了这个hostname。

Centos 6 修改主机的步骤：

1. Use the hostname utility

hostname myservernamehere

2. Alter the hostname in /etc/sysconfig/network

vi /etc/sysconfig/network

Change your old hostname by editing the text on the line after HOSTNAME=

3. Alter the hostname in /etc/hosts

vi /etc/hosts

If your old hostname is present here, edit it out and replace it with your new one.

4. reboot

由于已经安装了单机的 ORACLE 11g，先关闭数据库及监听再修改主机名称，然后重启主机。

修改监听文件

在重启主机之后，如果 ORACLE 的监听配置的是 hostname，同时也需要修改监听的配置文件/u01/app/oracle/product/19.3.0.0/dbhome_1/network/admin/listener.ora

LISTENER=
  (DESCRIPTION_LIST =
    (DESCRIPTION =
      (ADDRESS = (PROTOCOL = TCP)(HOST = 10.20.22.20)(PORT = 1521))
    )
)
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如果 host 里写的是 hostname，需要修改成新的hostname，或者直接写 IP地址。

OEM 无法启动问题处理

重启主机之后，启动监听、数据库都正常启动，但是 OEM 无法启动，会报 $ORACLE_HOME/oc4j/j2ee/OC4J_DBConsole_{new_hostname}_{db_name} not found. 这里想当然的是将这个目录重命名一下，将原来的 old_hostname 的目录重命名为now_hostname 的目录，但是又报 $ORACLE_HOME/now_hostname_dbname not found.同样也通过重命名的方式处理，但是仍然不行，在启动的时候，https的url 仍然是 old_hostname，也就是并不是重命名文件夹能解决的。

oracle@now_hostname:/home/oracle $emctl start dbconsole
OC4J Configuration issue. /u01/app/oracle/product/11.2.0.4/dbhome_1/oc4j/j2ee/OC4J_DBConsole_{newhostname}_{db_name} not found. 
oracle@now_hostname:/home/oracle $cd /u01/app/oracle/product/11.2.0.4/dbhome_1/oc4j/j2ee/
oracle@now_hostname:/u01/app/oracle/product/11.2.0.4/dbhome_1/oc4j/j2ee $ll
total 32
-rw-r--r--  1 oracle dba 1015 Feb 24  2024 deploy_db_wf.ini
drwxr-xr-x 14 oracle dba 4096 Feb 24  2024 home
drwxr-xr-x  3 oracle dba 4096 Feb 24  2024 oc4j_applications
drwxr-x---  6 oracle dba 4096 Feb 24  2024 OC4J_DBConsole
drwxr-xr-x 10 oracle dba 4096 Feb 26  2024 OC4J_DBConsole_old_hostname_dbname
drwxr-xr-x  5 oracle dba 4096 Feb 24  2024 OC4J_Workflow_Component_Container
drwxr-xr-x  5 oracle dba 4096 Feb 24  2024 OC4J_Workflow_Management_Container
drwxr-xr-x  2 oracle dba 4096 Feb 24  2024 utilities
oracle@now_hostname:/u01/app/oracle/product/11.2.0.4/dbhome_1/oc4j/j2ee $mv OC4J_DBConsole_old_hostname_dbname OC4J_DBConsole_dbname_dbname
oracle@now_hostname:/u01/app/oracle/product/11.2.0.4/dbhome_1/oc4j/j2ee $emctl start dbconsole
EM Configuration issue. /u01/app/oracle/product/11.2.0.4/dbhome_1/new_hostname_dbname not found. 
oracle@now_hostname:/u01/app/oracle/product/11.2.0.4/dbhome_1/oc4j/j2ee $cd /u01/app/oracle/product/11.2.0.4/dbhome_1/

oracle@now_hostname:/u01/app/oracle/product/11.2.0.4/dbhome_1 $mv old_hostname_dbname/ new_hostname_dbname
oracle@now_hostname:/u01/app/oracle/product/11.2.0.4/dbhome_1 $emctl start dbconsole
Oracle Enterprise Manager 11g Database Control Release 11.2.0.4.0 
Copyright (c) 1996, 2013 Oracle Corporation.  All rights reserved.
https://old hostname:1158/em/console/aboutApplication
Starting Oracle Enterprise Manager 11g Database Control ..................................^C

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这里通过重建 OEM 的方式来解决，注意，重建OEM的时候，要把上面重命名的文件夹进行删除，不然重建仍然不成功。

重建 OEM

emca -config dbcontrol db -repos recreate
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oracle@now_hostname:/home/oracle $emca -config dbcontrol db -repos recreate
 
STARTED EMCA at Sep 1, 2024 10:09:00 PM
EM Configuration Assistant, Version 11.2.0.3.0 Production
Copyright (c) 2003, 2011, Oracle.  All rights reserved.

Enter the following information:
Database SID: ORACLE_SID
Listener port number: 1521
Listener ORACLE_HOME [ /u01/app/oracle/product/11.2.0.4/dbhome_1 ]: 
Password for SYS user:  xxxxxxx
Password for DBSNMP user:  xxxxxx
Password for SYSMAN user:  xxxxxx
Email address for notifications (optional): 
Outgoing Mail (SMTP) server for notifications (optional): 
-----------------------------------------------------------------

You have specified the following settings

Database ORACLE_HOME ................ /u01/app/oracle/product/11.2.0.4/dbhome_1

Local hostname ................ new_hostname
Listener ORACLE_HOME ................ /u01/app/oracle/product/11.2.0.4/dbhome_1
Listener port number ................ 1521
Database SID ................ ORACLE_SID
Email address for notifications ............... 
Outgoing Mail (SMTP) server for notifications ............... 

-----------------------------------------------------------------
----------------------------------------------------------------------
WARNING : While repository is dropped the database will be put in quiesce mode.
----------------------------------------------------------------------
Do you wish to continue? [yes(Y)/no(N)]: y
Sep 1, 2024 10:09:36 PM oracle.sysman.emcp.EMConfig perform
INFO: This operation is being logged at /u01/app/oracle/cfgtoollogs/emca/db_name/emca_2024_09_01_22_09_00.log.
Sep 1, 2024 10:09:36 PM oracle.sysman.emcp.EMReposConfig invoke
INFO: Dropping the EM repository (this may take a while) ...
Sep 1, 2024 10:10:09 PM oracle.sysman.emcp.EMReposConfig invoke
INFO: Repository successfully dropped
Sep 1, 2024 10:10:09 PM oracle.sysman.emcp.EMReposConfig createRepository
INFO: Creating the EM repository (this may take a while) ...
Sep 1, 2024 10:12:10 PM oracle.sysman.emcp.EMReposConfig invoke
INFO: Repository successfully created
Sep 1, 2024 10:12:11 PM oracle.sysman.emcp.EMReposConfig uploadConfigDataToRepository
INFO: Uploading configuration data to EM repository (this may take a while) ...
Sep 1, 2024 10:12:38 PM oracle.sysman.emcp.EMReposConfig invoke
INFO: Uploaded configuration data successfully
Sep 1, 2024 10:12:39 PM oracle.sysman.emcp.util.DBControlUtil secureDBConsole
INFO: Securing Database Control (this may take a while) ...
Sep 1, 2024 10:13:31 PM oracle.sysman.emcp.util.DBControlUtil secureDBConsole
INFO: Database Control secured successfully.
Sep 1, 2024 10:13:31 PM oracle.sysman.emcp.util.DBControlUtil startOMS
INFO: Starting Database Control (this may take a while) ...
Sep 1, 2024 10:13:51 PM oracle.sysman.emcp.EMDBPostConfig performConfiguration
INFO: Database Control started successfully
Sep 1, 2024 10:13:51 PM oracle.sysman.emcp.EMDBPostConfig performConfiguration
INFO: >>>>>>>>>>> The Database Control URL is https://new_hostname:1158/em <<<<<<<<<<<
Sep 1, 2024 10:14:07 PM oracle.sysman.emcp.EMDBPostConfig invoke
WARNING: 
************************  WARNING  ************************

Management Repository has been placed in secure mode wherein Enterprise Manager data will be encrypted.  The encryption key has been placed in the file: /u01/app/oracle/productzhi_dbname/sysman/config/emkey.ora. Ensure this file is backed up as the encrypted data will become unusable if this file is lost. 

***********************************************************
Enterprise Manager configuration completed successfully
FINISHED EMCA at Sep 1, 2024 10:14:07 PM
oracle@now_hostname:/home/oracle $emctl status dbconsole
Oracle Enterprise Manager 11g Database Control Release 11.2.0.4.0 
Copyright (c) 1996, 2013 Oracle Corporation.  All rights reserved.
https://new_hostname:1158/em/console/aboutApplication
Oracle Enterprise Manager 11g is running. 
------------------------------------------------------------------
Logs are generated in directory /u01/app/oracle/product/11.2.0.4/dbhome_1/now_hostname_dbname/sysman/log 
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解决方案

重建 OEM

emca -config dbcontrol db -repos recreate
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参考文档

https://docs.redhat.com/en/documentation/red_hat_enterprise_linux/8/html/configuring_and_managing_networking/assembly_changing-a-hostname_configuring-and-managing-networking#proc_changing-a-hostname-using-hostnamectl_assembly_changing-a-hostname

oem